mDNS Repeater

Starting with VyOS 1.2 a Multicast DNS (mDNS) repeater functionality is provided.

Multicast DNS uses the 224.0.0.51 address, which is “administratively scoped” and does not leave the subnet. It re-broadcast mDNS packets from one interface to other interfaces. This enables support for e.g. Apple Airplay devices across multiple VLANs.

Since the mDNS protocol sends the AA records in the packet itself, the repeater does not need to forge the source address. Instead, the source address is of the interface that repeats the packet.

set service mdns repeater interface <interface>

To enable mDNS repeater you need to configure at least two interfaces. To re- broadcast all mDNS packets from eth0 to eth1 and vice versa run:

set service mdns repeater interface 'eth0'
set service mdns repeater interface 'eth1'
set service mdns repeater disable

mDNS repeater can be temporarily disabled without deleting the service using

Note

You can not run this in a VRRP setup, if multiple mDNS repeaters are launched in a subnet you will experience the mDNS packet storm death!